diff --git a/console/java17/src/main/java/tech/uom/demo/java17/format/TemperatureQuantityConverterDemo.java b/console/java17/src/main/java/tech/uom/demo/java17/format/TemperatureQuantityConverterDemo.java
index d93ff7d8..895248a9 100644
--- a/console/java17/src/main/java/tech/uom/demo/java17/format/TemperatureQuantityConverterDemo.java
+++ b/console/java17/src/main/java/tech/uom/demo/java17/format/TemperatureQuantityConverterDemo.java
@@ -1,28 +1,42 @@
 package tech.uom.demo.java17.format;
 
-import static javax.measure.Quantity.Scale.ABSOLUTE;
+import static javax.measure.Quantity.Scale.*;
 import static tech.units.indriya.unit.Units.CELSIUS;
 
+import java.text.NumberFormat;
+
 import javax.measure.Quantity;
 import javax.measure.Unit;
 import javax.measure.quantity.Temperature;
 
-import tech.units.indriya.quantity.Quantities;
-import tech.units.indriya.format.EBNFUnitFormat;
+import tech.units.indriya.format.NumberDelimiterQuantityFormat;
 import tech.units.indriya.format.SimpleUnitFormat;
+import tech.units.indriya.quantity.Quantities;
 
 public class TemperatureQuantityConverterDemo {
 	public static void main(String[] args) {
 		//Unit<Temperature> cByTen = CELSIUS.divide(10);
-		//var format = EBNFUnitFormat.getInstance();
 		var format = SimpleUnitFormat.getInstance();
 		Unit<Temperature> cByTen = format.parse("°C/10").asType(Temperature.class);
 		Quantity<Temperature> absT = Quantities.getQuantity(0d, CELSIUS, ABSOLUTE);
 		Quantity<Temperature> absT2 = Quantities.getQuantity(0d, CELSIUS, ABSOLUTE);
-		Quantity<Temperature> absT3 = Quantities.getQuantity(0d, cByTen, ABSOLUTE);
-		Quantity<Temperature> sum = absT.add(absT2);
-		System.out.println(sum);
-		System.out.println(absT3);
-		System.out.println(sum.to(cByTen));
+		Quantity<Temperature> relT = Quantities.getQuantity(0d, CELSIUS, RELATIVE);
+		Quantity<Temperature> relT2 = Quantities.getQuantity(0d, CELSIUS, RELATIVE);
+		Quantity<Temperature> sumAbs = absT.add(absT2);
+		Quantity<Temperature> sumRel = relT.add(relT2);
+		System.out.println(sumAbs);
+		System.out.println(sumRel);		
+		System.out.printf("Abs: %s%s", sumAbs.to(cByTen), System.lineSeparator());
+		System.out.printf("Rel: %s%s", sumRel.to(cByTen), System.lineSeparator());
+		
+		var qformat = NumberDelimiterQuantityFormat.getInstance(NumberFormat.getInstance(), format);
+        var source =  format.parse("K/10");
+        var intermediary = format.parse("K");
+		
+		var qs = Quantities.getQuantity(10, source, ABSOLUTE);
+		System.out.println(qformat.format(qs));
+		var qs3 = Quantities.getQuantity(1, intermediary,  ABSOLUTE);
+		var qs4 = qs.multiply(qs3);
+		System.out.println(qformat.format(qs4));
 	}
 }
diff --git a/console/java17/src/main/java/tech/uom/demo/java17/format/TemperatureUnitConverterDemo.java b/console/java17/src/main/java/tech/uom/demo/java17/format/TemperatureUnitConverterDemo.java
index 0bf0579a..f8054264 100644
--- a/console/java17/src/main/java/tech/uom/demo/java17/format/TemperatureUnitConverterDemo.java
+++ b/console/java17/src/main/java/tech/uom/demo/java17/format/TemperatureUnitConverterDemo.java
@@ -2,56 +2,36 @@
 
 import static javax.measure.Quantity.Scale.*;
 
-import java.text.NumberFormat;
-
 import javax.measure.IncommensurableException;
-import javax.measure.UnconvertibleException;
 import javax.measure.UnitConverter;
-import javax.measure.spi.ServiceProvider;
 
 import tech.units.indriya.AbstractUnit;
 import tech.units.indriya.format.EBNFUnitFormat;
-import tech.units.indriya.format.NumberDelimiterQuantityFormat;
-import tech.units.indriya.quantity.Quantities;
 
 public class TemperatureUnitConverterDemo {
 
 	public static void main(String[] args) {
 		//var format = ServiceProvider.current().getFormatService().getUnitFormat();
 		var format = EBNFUnitFormat.getInstance();
-		var format2 = NumberDelimiterQuantityFormat.getInstance(NumberFormat.getInstance(), format);
         var source =  format.parse("K/10");
-        var intermediary = format.parse("K");
+        var dest = format.parse("K");
         var source2 =  format.parse("°C/10");
-        var dest = format.parse("°C");
+        var dest2 = format.parse("°C");
         UnitConverter converter = null;
         UnitConverter converter2 = null;
-        UnitConverter converter3 = null;
         try {
-			converter = source.getConverterToAny(intermediary);
-			converter2 = dest.getConverterToAny(intermediary);
-			converter3 = ((AbstractUnit<?>)source2).getConverterToAny(dest, RELATIVE);
-		} catch (UnconvertibleException | IncommensurableException e) {
+			converter = source.getConverterToAny(dest);
+			converter2 = ((AbstractUnit<?>)source2).getConverterToAny(dest2, RELATIVE);
+		} catch (IncommensurableException e) {
 			e.printStackTrace();
 		}
 		if (converter != null) {
-			var toK = converter2.convert(1);
-			var converted = converter.convert(toK);
+			var converted = converter.convert(10);
 			System.out.println(converted);			
 		}
-		if (converter3 != null) {
-			var converted = converter3.convert(10);
-			System.out.println(converted);
-		}
-		
-		var qs = Quantities.getQuantity(10, source, ABSOLUTE);
-		System.out.println(format2.format(qs));
-		//var qs2 = Quantities.getQuantity(10, source2, Scale.ABSOLUTE);
-		//System.out.println(format2.format(qs2));
-		var qs3 = Quantities.getQuantity(1, intermediary,  ABSOLUTE);
-		var qs4 = qs.multiply(qs3);
-		System.out.println(format2.format(qs4));
-		//var qs5 = qs.to(dest);
+		if (converter2 != null) {
+			var converted2 = converter2.convert(10);
+			System.out.println(converted2);
+		}		
 	}
-
 }
diff --git a/lang/valhalla/pom.xml b/lang/valhalla/pom.xml
index c929c7f4..dc370ed9 100644
--- a/lang/valhalla/pom.xml
+++ b/lang/valhalla/pom.xml
@@ -11,7 +11,7 @@
 	<artifactId>valhalla</artifactId>
 	<name>Project Valhalla Demos</name>
 	<properties>
-		<java.version>14</java.version>
+		<java.version>23</java.version>
 	</properties>
 	<build>
 		<plugins>
@@ -19,28 +19,32 @@
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-compiler-plugin</artifactId>
 				<configuration>
+<!--
 					<source>${java.version}</source>
 					<target>${java.version}</target>
 					<verbose>true</verbose>
 					<fork>true</fork>
 					<executable>${java.bin}/javac.exe</executable>
 					<compilerVersion>${java.version}</compilerVersion>
+					-->
+					<release>${java.version}</release>
+					<enablePreview>true</enablePreview>
 				</configuration>
 			</plugin>
 
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-surefire-plugin</artifactId>
-				<version>3.0.0-M3</version>
 				<configuration>
 					<jvm>${java.bin}/java.exe</jvm>
+					<argLine>--enable-preview</argLine>
 				</configuration>
 			</plugin>
 
 			<plugin>
 				<groupId>org.codehaus.mojo</groupId>
 				<artifactId>exec-maven-plugin</artifactId>
-				<version>1.3.2</version>
+				<version>1.6.0</version>
 				<executions>
 					<execution>
 						<goals>
@@ -49,11 +53,16 @@
 					</execution>
 				</executions>
 				<configuration>
-					<executable>${java.bin}/java.exe</executable>
+					<mainClass>tech.uom.demo.valhalla.ValhallaDemo</mainClass>
+					<!-- executable>${java.bin}/java.exe</executable -->
+					<commandlineArgs>--enable-preview</commandlineArgs>
 					<arguments>
+					    <argument>--enable-preview</argument>
+<!--					    
 						<argument>-classpath</argument>
 						<classpath />
 						<argument>tech.uom.demo.valhalla.ValhallaDemo</argument>
+-->						
 					</arguments>
 				</configuration>
 			</plugin>
@@ -71,12 +80,10 @@
 		<dependency>
 			<groupId>tech.uom.lib</groupId>
 			<artifactId>uom-lib-common</artifactId>
-			<version>${lib.version}</version>
 		</dependency>
 		<dependency>
 			<groupId>tech.units</groupId>
 			<artifactId>indriya</artifactId>
-			<version>${ri.version}</version>
 		</dependency>
 	</dependencies>
 
diff --git a/lang/valhalla/src/main/java/tech/uom/demo/valhalla/VUnit.java b/lang/valhalla/src/main/java/tech/uom/demo/valhalla/VUnit.java
index d9546e12..9d261902 100644
--- a/lang/valhalla/src/main/java/tech/uom/demo/valhalla/VUnit.java
+++ b/lang/valhalla/src/main/java/tech/uom/demo/valhalla/VUnit.java
@@ -3,8 +3,7 @@
 import javax.measure.*;
 import java.util.Map;
 
-public inline class VUnit<Q extends Quantity<Q>> implements Unit?<Q> {
-
+public value class VUnit<Q extends Quantity<Q>> implements Unit<Q> {
 
 		private final String x;
         private final String y;
@@ -44,21 +43,6 @@ public Map<? extends Unit<?>, Integer> getBaseUnits() {
         return null;
     }
 
-    @Override
-    public boolean isCompatible(Unit<?> that) {
-        return false;
-    }
-
-    @Override
-    public <T extends Quantity<T>> Unit<T> asType(Class<T> type) throws ClassCastException {
-        return null;
-    }
-
-    @Override
-    public UnitConverter getConverterToAny(Unit<?> that) throws IncommensurableException, UnconvertibleException {
-        return null;
-    }
-
     @Override
     public Unit<Q> alternate(String symbol) {
         return null;
@@ -84,11 +68,6 @@ public Unit<Q> multiply(double multiplier) {
         return null;
     }
 
-    @Override
-    public Unit<?> multiply(Unit<?> multiplier) {
-        return null;
-    }
-
     @Override
     public Unit<?> inverse() {
         return null;
@@ -104,10 +83,6 @@ public Unit<Q> divide(double divisor) {
         return null;
     }
 
-    @Override
-    public Unit<?> divide(Unit<?> divisor) {
-        return null;
-    }
 
     @Override
     public Unit<?> root(int n) {
@@ -129,14 +104,51 @@ public Unit<Q> prefix(Prefix prefix) {
         return null;
     }
 
-    @Override
-    public UnitConverter getConverterTo(Unit<Q> that) throws UnconvertibleException {
-        return null;
-    }
-    
     @Override
     public String toString() {
     	return "VUnit [symbol=" + x + ", name=" + y + "]";
     }
 
+	@Override
+	public boolean isEquivalentTo(Unit that) {
+		// TODO Auto-generated method stub
+		return false;
+	}
+
+	@Override
+	public boolean isCompatible(Unit that) {
+		// TODO Auto-generated method stub
+		return false;
+	}
+
+	@Override
+	public Unit asType(Class type) throws ClassCastException {
+		// TODO Auto-generated method stub
+		return null;
+	}
+
+	@Override
+	public UnitConverter getConverterTo(Unit that) throws UnconvertibleException {
+		// TODO Auto-generated method stub
+		return null;
+	}
+
+	@Override
+	public UnitConverter getConverterToAny(Unit that) throws IncommensurableException, UnconvertibleException {
+		// TODO Auto-generated method stub
+		return null;
+	}
+
+	@Override
+	public Unit multiply(Unit multiplier) {
+		// TODO Auto-generated method stub
+		return null;
+	}
+
+	@Override
+	public Unit divide(Unit divisor) {
+		// TODO Auto-generated method stub
+		return null;
+	}
+
 }
diff --git a/lang/valhalla/src/main/java/tech/uom/demo/valhalla/ValhallaDemo.java b/lang/valhalla/src/main/java/tech/uom/demo/valhalla/ValhallaDemo.java
index df9b6989..5743c2ab 100644
--- a/lang/valhalla/src/main/java/tech/uom/demo/valhalla/ValhallaDemo.java
+++ b/lang/valhalla/src/main/java/tech/uom/demo/valhalla/ValhallaDemo.java
@@ -1,13 +1,15 @@
 package tech.uom.demo.valhalla;
 
+import javax.measure.quantity.Mass;
+
 public class ValhallaDemo {
 	private static final String PATTERN = "%s and %s are %s.";
 	private static final String SAME = "the same";
 	private static final String NOT_SAME = "not the same";
 	
 	public static void main(String[] args) {
-        VUnit m1 = VUnit.of("kg","kilogram");
-        VUnit m2 = VUnit.of("kg","kilogram");
+        VUnit<Mass> m1 = VUnit.of("kg","kilogram");
+        VUnit<Mass> m2 = VUnit.of("kg","kilogram");
         System.out.println(m1);
         if (m1 == m2) {
         	System.out.println(String.format(PATTERN, m1, m2, SAME));
diff --git a/lang/valhalla/src/test/java/tech/uom/demo/valhalla/EqualityTest.java b/lang/valhalla/src/test/java/tech/uom/demo/valhalla/EqualityTest.java
index 2a77b10d..eedbe1a4 100644
--- a/lang/valhalla/src/test/java/tech/uom/demo/valhalla/EqualityTest.java
+++ b/lang/valhalla/src/test/java/tech/uom/demo/valhalla/EqualityTest.java
@@ -1,12 +1,17 @@
 package tech.uom.demo.valhalla;
 
-import static org.junit.Assert.*;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 	/*
 	 * @test
-	 * @summary Test inline classes for equality
+	 * @summary Test value classes for equality
 	 */
 	public class EqualityTest {
 
diff --git a/lang/valhalla/src/test/java/tech/uom/demo/valhalla/InlineReferenceTest.java b/lang/valhalla/src/test/java/tech/uom/demo/valhalla/InlineReferenceTest.java
index 59752b13..bed62004 100644
--- a/lang/valhalla/src/test/java/tech/uom/demo/valhalla/InlineReferenceTest.java
+++ b/lang/valhalla/src/test/java/tech/uom/demo/valhalla/InlineReferenceTest.java
@@ -1,11 +1,9 @@
 package tech.uom.demo.valhalla;
 
-import static org.junit.Assert.*;
 
 import java.lang.ref.ReferenceQueue;
 import java.lang.ref.WeakReference;
 
-import org.junit.Test;
 
 	/*
 	 * @test
@@ -14,17 +12,17 @@
 	 */
 	public class InlineReferenceTest {
 
-	    @Test(expected = IllegalArgumentException.class)
-	    public void test1() {
-	        VUnit? p = VUnit.of("k","kilogram");
-	        WeakReference<VUnit?> r = new WeakReference<>(p);
-	    }
-
-	    @Test(expected = IllegalArgumentException.class)
-	    public void test2() {
-	        ReferenceQueue<Object> q = new ReferenceQueue<>();
-	        VUnit? p = VUnit.of("k","kilogram");
-	        WeakReference<VUnit?> r = new WeakReference<>(p, q);
-	    }
+//	    @Test(expected = IllegalArgumentException.class)
+//	    public void test1() {
+//	        VUnit? p = VUnit.of("k","kilogram");
+//	        WeakReference<VUnit?> r = new WeakReference<>(p);
+//	    }
+//
+//	    @Test(expected = IllegalArgumentException.class)
+//	    public void test2() {
+//	        ReferenceQueue<Object> q = new ReferenceQueue<>();
+//	        VUnit? p = VUnit.of("k","kilogram");
+//	        WeakReference<VUnit?> r = new WeakReference<>(p, q);
+//	    }
 
 }
diff --git a/lang/valhalla/src/test/java/tech/uom/demo/valhalla/MethodTest.java b/lang/valhalla/src/test/java/tech/uom/demo/valhalla/MethodTest.java
index 4cd63d7e..1bbc842b 100644
--- a/lang/valhalla/src/test/java/tech/uom/demo/valhalla/MethodTest.java
+++ b/lang/valhalla/src/test/java/tech/uom/demo/valhalla/MethodTest.java
@@ -1,12 +1,15 @@
 package tech.uom.demo.valhalla;
 
-import static org.junit.Assert.*;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 	/*
 	 * @test
-	 * @summary Test inline classes and its methods
+	 * @summary Test value classes and their methods
 	 */
 	public class MethodTest {